Which sentence shows the correct verb mood usage?

it is essential that she wait in line.
if we wait now, we were next in line.
go be waiting in line.
since we know about the sale, we were going to get here sooner.

(mc)

which word creates the verb mood error in this sentence: "if i was able to do it all over again, i would study the week before the test"?

would
do
was
study

The sentence that shows the correct verb mood usage is option A.

It is essential that she waits in line.

The word that creates the verb mood error in the sentence is "was".

There, there should be a WERE. Or a could: If I could do it all over again...

That sentence is a conditional. In this case a second conditional.

The First Conditional:

(if + present simple, ... will + infinitive)

If it rains tomorrow, we'll go to the cinema.

The Second Conditional:

(if + past simple, ... would + infinitive)

If I had a lot of money, I would travel around the world.

In the second conditional, when the verb in the if-clause is a form of be, we use were instead of was.

that is the way of a cheater and cheaters get nothing but bad grades and in trouble.

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